Have you noticed if the crop empties? Is she pooping?
Some chicks do seem to have a bigger appetite than others and the crop size can look alarming. As long as she is drinking/eating well, is active and doing little chickie things with the others, she is fine.
When to worry, is if she stands off to herself acts lethargic and is not interested in food/water.
They can be quite piggish at times. It's always a good idea to check and monitor crops, so you are doing the right thing there. Even with my adults, I check their crop function weekly, so I can catch anything going on early (full at night/empty in the morning).
I hope you enjoy your babies! She sure is a cute little thing